Lost in Space is a science fiction TV series created and produced by Irwin Allen, filmed by 20th Century Fox Television, and broadcast on CBS. The show ran for three seasons, with 83 episodes airing between September 15, 1965, and March 6, 1968. Their first TV season was filmed in black and white, but the rest of them were filmed in color. In 1998, a Lost in Space movie, based on the TV series, was released. Though the TV series centered around the "Robinson" family, storylines focused primarily on Jonathan Harris as Dr. Zachary Smith; originally an utterly evil would-be killer who as the first season progressed became a sympathetic anti-hero, providing comic relief to the TV show (and causing most of the episodic problems).

The TV series is an adaptation of the novel The Swiss Family Robinson. The astronaut family of Dr. John Robinson, accompanied by an air force pilot and also a robot, set out from an overpopulated Earth in the spaceshipJupiter 2 to visit a planet circling the star Alpha Centauri with hopes of colonizing it. Their mission in 1997 (the official launch date of the Jupiter 2 was October 16, 1997) is immediately sabotaged by Dr. Zachary Smith, who slips aboard their spaceship and reprograms the robot to destroy the ship and crew. Smith is trapped aboard, saving himself by prematurely reviving the crew from suspended animation. They save the ship, but consequent damage leaves them lost in space. Eventually they crash on an alien world, later identified as Priplanis, where they must survive a host of adventures. Smith (whom Allen originally intended to kill off) remains through the series as a source of comedic cowardice and villainy, exploiting the forgiving (or forgetful) nature of the Robinsons.

At the start of the second season, the repaired Jupiter 2 launches again, but after two episodes the Robinsons crash on another planet and spend the season there. This replicated the feel of the first season, although by this time the focus of the series was more on humor than straight action/adventure.

In the third season, the Robinson Family wasn't restricted to one world. The now mobile Jupiter-2 would travel to other worlds in an attempt to return to Earth or to settle on Alpha Centauri. The Space Pod was added as a means of transportation between the ship and planets. This season had a dramatically different opening credits sequence.